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                                                                     Exhibit 4.1


                                                                  EXECUTION COPY



                            CENTURY ALUMINUM COMPANY

                                  $325,000,000
              11 3/4% SENIOR SECURED FIRST MORTGAGE NOTES DUE 2008



                               PURCHASE AGREEMENT



March 28, 2001
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                                                            March 28, 2001


Credit Suisse First Boston Corporation
Fleet Securities, Inc.
c/o   Credit Suisse First Boston Corporation
      Eleven Madison Avenue
      New York, New York 10010-3629

Dear Sirs and Mesdames:

         Century Aluminum Company, a Delaware corporation (the "COMPANY"),
proposes to issue and sell to Credit Suisse First Boston Corporation ("CSFBC")
and Fleet Securities, Inc. (the "INITIAL PURCHASERS") $325,000,000 principal
amount of its 11 3/4% Senior Secured First Mortgage Notes due 2008 (the
"SECURITIES") to be issued pursuant to the provisions of an Indenture (the
"INDENTURE") among the Company, the Guarantors referred to below and Wilmington
Trust Company, as Trustee (the "TRUSTEE").

         The Securities will be unconditionally guaranteed as to payment of
principal, premium, if any, and interest, by each of the guarantors listed on
the signature pages hereof (the "OWNED GUARANTORS") and Metalsco Ltd., Skyliner,
Inc. and NSA, Ltd. (the "ACQUIRED GUARANTORS" and, together with the Owned
Guarantors, the "GUARANTORS"). The Securities will be secured by perfected liens
on (i) a cash collateral account and all amounts and investments held therein
and (ii) certain of the property, plant and equipment held by certain of the
Guarantors pursuant to the documents listed on Schedule III hereto (the
"SECURITY DOCUMENTS").

         The Securities will be offered without being registered under the
Securities Act of 1933, as amended (the "SECURITIES ACT"), to qualified
institutional buyers in compliance with the exemption from registration provided
by Rule 144A under the Securities Act and in offshore transactions in reliance
on Regulation S under the Securities Act ("REGULATION S"). The Initial
Purchasers and their direct and indirect transferees will be entitled to the
benefits of a Registration Rights Agreement dated the Closing Date (as defined
in Section 4) among the Company, the Guarantors and the Initial Purchasers (the
"REGISTRATION RIGHTS AGREEMENT").

         In connection with the sale of the Securities, the Company has prepared
a preliminary offering circular (the "PRELIMINARY OFFERING CIRCULAR") and will
prepare a final offering circular (the "FINAL OFFERING CIRCULAR" and, with the
Preliminary Offering Circular, each an "OFFERING CIRCULAR") including or
incorporating by reference a description of the terms of the Securities, the
terms of the offering and a description of the Company. As used herein, the term
"Offering Circular" shall include in each case the documents incorporated by
reference therein. The terms "SUPPLEMENT", "AMENDMENT" and "AMEND" as used
herein with respect to an Offering Circular shall include all documents deemed
to be incorporated by reference in the Preliminary Offering Circular or Final
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Offering Circular that are filed subsequent to the date of such Offering
Circular with the Securities and Exchange Commission (the "COMMISSION") pursuant
to the Securities Exchange Act of 1934, as amended (the "EXCHANGE ACT") until
all of the Securities have been sold.

         It is understood and agreed that on or prior to the Closing Date, the
Company will consummate the following transactions (collectively, the
"TRANSACTIONS"), all as more fully described in the Offering Circulars:

                  (i) (A) pursuant to a stock purchase agreement dated as of
         August 31, 2000 (the "ACQUISITION AGREEMENT") between the Company and
         Southwire Company, the Company will acquire all of the outstanding
         common stock of Metalsco, Ltd. and certain other assets and rights
         related to the NSA aluminum reduction plant located in Hawesville,
         Kentucky, owned by NSA, Ltd. ("NSA") (collectively, the "ACQUISITION")
         and (B) pursuant to an asset purchase agreement between Glencore
         Acquisition I LLC, a subsidiary of Glencore AG (the "GLENCORE BUYER")
         and NSA (the "GLENCORE DISPOSITION AGREEMENT and, together with the
         Acquisition Agreement, the "ACQUISITION AGREEMENTS"), the Company will,
         immediately following the closing under the Acquisition Agreement,
         cause NSA to convey all right, title and interest to potline no. 5 at
         the Hawesville facility and a 20% undivided interest in all remaining
         property owned by NSA (other than potlines no. 1, 2, 3 and 4) and the
         Company will convey a 20% interest in Century Aluminum of Kentucky,
         LLC, the operator of the Hawesville facility (the "OPERATOR"), in each
         case to Glencore or one of its subsidiaries (the "GLENCORE
         DISPOSITION");

                  (ii) the Company will repay any amounts outstanding, and
         terminate the commitments, under its credit agreement dated as of March
         31, 1999 between the Company, the lenders party thereto and BankBoston,
         N.A. and CIT Group/Business Credit, Inc. as agents (together with any
         related guaranties, security agreements and other instruments and
         agreements, the "EXISTING CREDIT FACILITY"),

                  (iii) the Company will enter into a revolving loan facility
         (together with any related guaranties, security agreements and other
         instruments and agreements, the "NEW CREDIT FACILITY") on substantially
         the terms described in the Offering Circulars, and borrow approximately
         $4.7 million of revolving loans thereunder,

                  (iv) pursuant to a convertible preferred stock purchase
         agreement (the "PREFERRED STOCK PURCHASE AGREEMENT") between the
         Company and Glencore AG, the Company will issue in the aggregate
         $25,000,000 of its 8% Cumulative Convertible Preferred Stock (the
         "PREFERRED STOCK"), par value $50.00 per share, to Glencore AG without
         registering the Preferred Stock under the Securities Act in reliance
         upon the exemption from registration provided by Section 4(2) of the
         Securities Act and/or Regulation S under the Securities Act, and

                  (v) the Company will issue and sell the Securities pursuant to
         this Agreement and the Indenture, and the Company and the Guarantors
         will create the security interests provided for in the Security
         Documents.


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         This Agreement (including the Assumption Agreement, in the form of
Exhibit D hereto, under which the Acquired Guarantors will become a party
hereto), the Indenture, the Registration Rights Agreement, the New Credit
Facility, the Acquisition Agreements, the Security Documents, the Preferred
Stock Purchase Agreement, the Owners Agreement between NSA, the Glencore Buyer
and the Operator (the "HAWESVILLE OWNERS AGREEMENT") and the Related Agreements
(as defined in the Acquisition Agreement) are collectively referred to as the
"TRANSACTION DOCUMENTS". References herein to the Company's charter or
certificate of incorporation shall refer to the charter as amended by the
certificate of designation (the "CERTIFICATE OF DESIGNATION") with respect to
the Preferred Stock.

         1. Representations and Warranties. The Company and the Guarantors
jointly and severally represent and warrant to, and agree with, you that:

                  (a) (i) Each document, if any, filed or to be filed pursuant
         to the Exchange Act and incorporated by reference in either Offering
         Circular complied or will comply when so filed in all material respects
         with the Exchange Act and the applicable rules and regulations of the
         Commission thereunder and (ii) the Preliminary Offering Circular, as of
         the date thereof, did not contain and the Final Offering Circular, in
         the form used by the Initial Purchasers to confirm sales as of the date
         hereof and on the Closing Date (as defined in Section 5), will not
         contain any untrue statement of a material fact or omit to state a
         material fact necessary to make the statements therein, in the light of
         the circumstances under which they were made, not misleading, except
         that the representations and warranties set forth in this paragraph do
         not apply to statements or omissions in either Offering Circular based
         upon information relating to any Initial Purchaser furnished to the
         Company in writing by such Initial Purchaser through you expressly for
         use therein.

                  (b) The Company has been duly incorporated, is validly
         existing as a corporation in good standing under the laws of the
         jurisdiction of its incorporation, has the corporate power and
         authority to own its property and to conduct its business as described
         in each Offering Circular and is duly qualified to transact business
         and is in good standing in each jurisdiction in which the conduct of
         its business or its ownership or leasing of property requires such
         qualification, except to the extent that the failure to be so qualified
         or be in good standing would not have a material adverse effect on the
         Company and its subsidiaries, taken as a whole.

                  (c) Each person that will be a subsidiary of the Company as of
         the Closing Date (each, a "SUBSIDIARY") has been duly organized, is
         validly existing in good standing under the laws of the jurisdiction of
         its organization, has the corporate or other power and authority to own
         its property and to conduct its business as described in each Offering
         Circular and is duly qualified to transact business and is in good
         standing in each jurisdiction in which the conduct of its business or
         its ownership or leasing of property requires such qualification,
         except to the extent that the failure to be so qualified or be in good
         standing would not have a material adverse effect on the Company and
         its subsidiaries, taken as a whole; all of


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         the issued shares of capital stock of each subsidiary of the Company
         have been duly and validly authorized and issued, are fully paid and
         non-assessable and are owned directly or indirectly by the Company,
         free and clear of all liens, encumbrances, equities or claims except
         (i) for liens under the Existing Credit Facility, which will be
         released on the Closing Date, (ii) for encumbrances on the Company's
         ability to dispose of the stock of Berkeley Aluminum, Inc. and NSA,
         Ltd. pursuant to (x) the Amended and Restated Owners' Agreement dated
         as of January 26, 1996 between Alumax of South Carolina, Inc. and
         Berkeley Aluminum, Inc., as amended heretofore (the "MT. HOLLY OWNERS
         AGREEMENT"), governing the use and ownership of the Mt. Holly facility
         and (y) the Hawesville Owners Agreement, in each case as disclosed in
         the Offering Circulars, (iii) that the capital stock of each Acquired
         Guarantor is owned by Southwire Company prior to the Closing Date and
         (iv) as otherwise disclosed in each Offering Circular.

                  (d) This Agreement has been duly authorized, executed and
         delivered by the Company and each Owned Guarantor, and as of the
         Closing Date, the Assumption Agreement will have been duly authorized,
         executed and delivered by each Acquired Guarantor.

                  (e) The Securities have been duly authorized and, when
         executed and authenticated in accordance with the provisions of the
         Indenture and delivered to and paid for by the Initial Purchasers in
         accordance with the terms of this Agreement, will be valid and binding
         obligations of the Company, enforceable in accordance with their terms,
         subject to the effects of applicable bankruptcy, insolvency and similar
         laws affecting creditors' rights generally and equitable principles of
         general applicability, and will be entitled to the benefits of the
         Indenture and the Registration Rights Agreement (regardless of whether
         considered in an action at law or in equity).

                  (f) Each Owned Guarantor has duly authorized its Guarantee of
         the Securities and, as of the Closing Date, each Acquired Guarantor
         will have duly authorized its Guarantee of the Securities and, when the
         Securities are executed and authenticated in accordance with the
         provisions of the Indenture and delivered to and paid for by the
         Initial Purchasers in accordance with the terms of this Agreement, such
         Guarantee will be a valid and binding obligation of such Guarantor,
         enforceable in accordance with its terms, subject to applicable
         bankruptcy, insolvency or similar laws affecting creditors' rights
         generally and general principles of equity (regardless of whether
         considered in an action at law or in equity).

                  (g) The Preferred Stock has been duly authorized and, when
         issued and delivered in accordance with the terms thereof, will be
         validly issued, fully paid and non-assessable.

                  (h) Each of the Transaction Documents (other than this
         Agreement and the Assumption Agreement) has been duly authorized by the
         Company and each of its subsidiaries party thereto (other than the
         Acquired Guarantors) and, as of the Closing Date, each of such
         documents


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         will have been duly authorized by each Acquired Guarantor, and when
         executed and delivered by the Company or such subsidiaries, will be a
         valid and binding obligation of each such person, enforceable in
         accordance with its terms, subject to applicable bankruptcy, insolvency
         or similar laws affecting creditors' rights generally and general
         principles of equity (regardless of whether considered in an action at
         law or in equity) and to the extent that rights to indemnity may be
         limited by federal or state securities laws or the public policy
         underlying such laws.

                  (i) The execution and delivery by the Company and each of its
         subsidiaries of, and the performance by the Company and each of its
         subsidiaries of its obligations under, the Transaction Documents to
         which it is or will be a party and the consummation of the Transactions
         will not contravene (A) any provision of applicable law, (B) the
         certificate of incorporation or by-laws of the Company or any of its
         subsidiaries, (C) any agreement or other instrument binding upon the
         Company or any of its subsidiaries or (D) any judgment, order or decree
         of any governmental body, agency or court having jurisdiction over the
         Company or any subsidiary except, in the case of (C) and (D), for
         contraventions that would not have a material adverse effect on the
         Company and its subsidiaries, taken as a whole; and no consent,
         approval, authorization or order of, or qualification with, any
         governmental body or agency is required for the performance by the
         Company or any of its subsidiaries of its obligations under the
         Transaction Documents or the consummation of the Transactions, except
         such as have been made and such as may be required by the securities or
         Blue Sky laws of the various states in connection with the offer and
         sale of the Securities (including the Guarantees) and by Federal and
         state securities laws with respect to the obligations of the Company
         and the Guarantors under the Registration Rights Agreement.

                  (j) Neither the Company nor any of its subsidiaries (i) is in
         violation of its respective charter or by-laws or similar
         organizational documents or (ii) is in default in the performance or
         observance of any obligation, agreement, covenant or condition
         contained in any bond, debenture, note or other evidence of
         indebtedness, or in any lease, contract, indenture, deed of trust, loan
         agreement, joint venture or other agreement or instrument to which the
         Company or any of its subsidiaries is a party, or by which it or any of
         its subsidiaries or their respective properties may be bound, except
         where such default would not have a material adverse effect on the
         Company and its subsidiaries, taken as a whole; and neither the Company
         nor any of its subsidiaries is in violation of any law, order, rule,
         regulation, writ, injunction, judgment or decree of any court,
         government or governmental agency or body, domestic or foreign, having
         jurisdiction over the Company or any of its subsidiaries or over their
         respective properties except where such violation would not have a
         material adverse effect on the Company and its subsidiaries, taken as a
         whole.

                  (k) (x)(i) Each of the contracts set forth on Schedule II-A
         (the "EXISTING MATERIAL CONTRACTS") has been duly authorized, executed
         and delivered by, and constitutes a valid and binding obligation of,
         the Company and/or its subsidiaries party thereto; (ii) each of the
         contracts


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         (the "NEW MATERIAL CONTRACTS") set forth in Schedule II-B has been duly
         authorized by the Company and each of its subsidiaries party thereto
         (other than the Acquired Guarantors) and, as of the Closing Date, will
         have been duly authorized by each Acquired Guarantor and, when executed
         and delivered by the Company and/or its subsidiaries party thereto,
         will be a valid and binding obligation of the Company and such
         subsidiaries; and (iii) the Company and/or its subsidiaries party
         thereto have duly authorized the assumption of each of the contracts
         (the "ASSIGNED MATERIAL CONTRACTS" and, together with the Existing
         Material Contracts and the New Material Contracts, the "MATERIAL
         CONTRACTS") set forth in Schedule II-C and, when such assumption (and
         any related assignment) has been duly executed and delivered, each
         Assigned Material Contract will be a valid and binding obligation of
         the Company and such subsidiaries; (y) each of the Existing Material
         Contracts is in full force and effect as of the date hereof and, as of
         the Closing Date, each of the Material Contracts will be in full force
         and effect; and (z) neither the Company nor any of its subsidiaries,
         nor, to the knowledge of the Company, any of the other parties thereto,
         is, or with the giving of notice or lapse of time or both would be, in
         violation of or in default under any of the Material Contracts, except
         for violations and defaults which individually or in the aggregate
         would not have a material adverse effect on the Company and its
         subsidiaries, taken as a whole.

                  (l) There has not occurred any material adverse change, or any
         development involving a prospective material adverse change, in the
         condition, financial or otherwise, or in the earnings, business or
         operations of the Company and its subsidiaries, taken as a whole, from
         that set forth in the Final Offering Circular (exclusive of any
         amendments or supplements hereto subsequent to the date of this
         Agreement).

                  (m) Except as described in each Offering Circular, there are
         no legal or governmental proceedings pending or, to the Company's
         knowledge, threatened to which the Company or any of its subsidiaries
         is a party or to which any of the properties of the Company or any of
         its subsidiaries is subject other than proceedings accurately described
         in all material respects in each Offering Circular and proceedings that
         would not reasonably be expected to have a material adverse effect on
         the Company and its subsidiaries, taken as a whole, or on the power
         (corporate or otherwise) or ability of the Company or any of its
         subsidiaries to perform its obligations under the Transaction Documents
         or to consummate the Transactions.

                  (n) The Company and its subsidiaries (i) are in compliance
         with any and all applicable foreign, federal, state and local laws and
         regulations relating to the protection of human health and safety, the
         environment or hazardous or toxic substances or wastes, pollutants or
         contaminants ("ENVIRONMENTAL LAWS"), (ii) have received all permits,
         licenses or other approvals required of them under applicable
         Environmental Laws to conduct their respective businesses and (iii) are
         in compliance with all terms and conditions of any such permit, license
         or approval, except where such noncompliance with Environmental Laws,
         failure to receive required permits, licenses or other approvals or
         failure to comply with the terms


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         and conditions of such permits, licenses or approvals would not, singly
         or in the aggregate, have a material adverse effect on the Company and
         its subsidiaries, taken as a whole, except in each case as described in
         each Offering Circular.

                  (o) Other than as described in the Offering Circulars, there
         are no costs or liabilities associated with Environmental Laws
         (including, without limitation, any capital or operating expenditures
         required for clean-up, closure of properties or compliance with
         Environmental Laws or any permit, license or approval, any related
         constraints on operating activities and any potential liabilities to
         third parties) which are not disclosed in the Offering Circulars and
         would, singly or in the aggregate, have a material adverse effect on
         the Company and its subsidiaries, taken as a whole.

                  (p) Subsequent to the date as of which information is given in
         the Final Offering Circular (exclusive of any amendment or supplement
         thereto subsequent to the date of this Agreement), (i) the Company and
         its subsidiaries have not incurred any material liability or
         obligation, direct or contingent, nor entered into any material
         transaction not in the ordinary course of business; (ii) the Company
         has not purchased any of its outstanding capital stock, nor declared,
         paid or otherwise made any dividend or distribution of any kind on its
         capital stock other than ordinary and customary dividends; and (iii)
         there has not been any material change in the capital stock, short-term
         debt or long-term debt of the Company and its subsidiaries, except in
         each case as described in the Offering Circulars.

                  (q) The Company and its subsidiaries have good and marketable
         title in fee simple to all real property owned by them and good and
         marketable title to all personal property owned by them, in each case
         which is material to the business of the Company and its subsidiaries,
         taken as a whole, in each case free and clear of all liens,
         encumbrances and defects except (A) liens thereon created pursuant to
         the Security Documents or the New Credit Facility and (B) such other
         liens, encumbrances and defects that do not in the aggregate materially
         affect the value of such property and do not materially interfere with
         the use made and proposed to be made of such property by the Company
         and its subsidiaries; and any real property and buildings held under
         lease by the Company and its subsidiaries are held by them under valid,
         subsisting and enforceable leases with such exceptions as are not
         material and do not materially interfere with the use made and proposed
         to be made of such property and buildings by the Company and its
         subsidiaries, in each case except as described in the Offering
         Circulars.

                  (r) The Company and its subsidiaries own or possess, or can
         acquire on reasonable terms, all material patents, patent rights,
         licenses, inventions, copyrights, know-how (including trade secrets and
         other unpatented and/or unpatentable proprietary or confidential
         information, systems or procedures), trademarks, service marks and
         trade names currently employed by them in connection with the business
         now operated by them, and neither the Company nor any of its
         subsidiaries has received any notice of infringement of or conflict
         with asserted rights of others with respect to any of the foregoing
         which, singly or in the aggregate, if the


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         subject of an unfavorable decision, ruling or finding, would have a
         material adverse effect on the Company and its subsidiaries, taken as a
         whole.

                  (s) No material labor dispute with the employees of the
         Company or any of its subsidiaries exists (except as described in the
         Offering Circulars), or, to the knowledge of the Company, is imminent;
         and the Company is not aware of any existing, threatened or imminent
         labor disturbance by the employees of any of its principal suppliers,
         manufacturers or contractors that could have a material adverse effect
         on the Company and its subsidiaries, taken as a whole.

                  (t) The Company and each of its subsidiaries are insured by
         insurers of recognized financial responsibility against such losses and
         risks and in such amounts as are prudent and customary in the
         businesses in which they are engaged; neither the Company nor any of
         its subsidiaries has been refused any insurance coverage sought or
         applied for; and neither the Company nor any of its subsidiaries has
         any reason to believe that it will not be able to renew its existing
         insurance coverage as and when such coverage expires or to obtain
         similar coverage from similar insurers as may be necessary to continue
         its business at a cost that would not have a material adverse effect on
         the Company and its subsidiaries, taken as a whole, except as described
         in the Offering Circulars.

                  (u) The Company and its subsidiaries possess all certificates,
         authorizations and permits issued by the appropriate federal, state or
         foreign regulatory authorities necessary to conduct their respective
         businesses, and have made all declarations and filings with, all
         federal, state, local and other governmental authorities (including
         foreign regulatory agencies), all self- regulatory organizations and
         all courts and other tribunals, domestic or foreign, necessary to own
         or lease, as the case may be, and to operate its properties and to
         carry on its business as conducted as of the date hereof, except such
         as would not result in a material adverse effect on the Company and its
         subsidiaries, taken as a whole, and neither the Company nor any of its
         subsidiaries has received any notice of proceedings relating to the
         revocation or modification of any such certificate, authorization or
         permit which, singly or in the aggregate, if the subject of an
         unfavorable decision, ruling or finding, would have a material adverse
         effect on the Company and its subsidiaries, taken as a whole, except as
         described in the Offering Circulars.

                  (v) The Company and each of its subsidiaries maintains a
         system of internal accounting controls sufficient to provide reasonable
         assurance that (i) transactions are executed in accordance with
         management's general or specific authorizations; (ii) transactions are
         recorded as necessary to permit preparation of financial statements in
         conformity with generally accepted accounting principles and to
         maintain asset accountability; (iii) access to assets is permitted only
         in accordance with management's general or specific authorization; and
         (iv) the recorded accountability for assets is compared with the
         existing assets at reasonable intervals and appropriate action is taken
         with respect to any differences.


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                  (w) The financial statements of the Company included in the
         Offering Circulars present fairly in all material respects the
         consolidated financial position of the Company and its existing
         subsidiaries as of the dates shown and their results of operations and
         cash flows for the periods shown, and such financial statements have
         been prepared in conformity with generally accepted accounting
         principles in the United States applied on a consistent basis; the
         financial statements of NSA, Ltd. included in the Offering Circulars
         present fairly in all material respects the financial position of NSA,
         Ltd. as of the dates shown and its results of operations for the
         periods shown, and such financial statements have been prepared in
         conformity with generally accepted accounting principles in the United
         States applied on a consistent basis; the financial statements of
         Xstrata Aluminum Corporation incorporated by reference in the Offering
         Circulars present fairly in all material respects the financial
         position of Xstrata Aluminum Corporation as of the dates shown and
         their results of operations and cash flows for the periods shown, and
         such financial statements have been prepared in conformity with
         generally accepted accounting principles in the United States applied
         on a consistent basis; and the assumptions used in preparing the pro
         forma financial statements included in the Offering Circulars provide a
         reasonable basis for presenting the material effects directly
         attributable to the transactions or events described therein, the
         related pro forma adjustments give appropriate effect to those
         assumptions, and the pro forma columns therein reflect the proper
         application of those adjustments to the corresponding historical
         financial statement amounts.

                  (x) Neither the Company nor any Guarantor is, and after giving
         effect to the offering and sale of the Securities and the application
         of the proceeds thereof as described in the Final Offering Circular
         neither will be, required to register as an "investment company" as
         such term is defined in the Investment Company Act of 1940, as amended.

                  (y) Neither the Company nor any affiliate (as defined in Rule
         501(b) of Regulation D under the Securities Act, an "AFFILIATE") of the
         Company has directly, or through any agent (other than the Initial
         Purchasers, as to whom the Company makes no representation), (i) sold,
         offered for sale, solicited offers to buy or otherwise negotiated in
         respect of, any security (as defined in the Securities Act) which is or
         will be integrated with the sale of the Securities in a manner that
         would require the registration under the Securities Act of the
         Securities or (ii) engaged in any form of general solicitation or
         general advertising in connection with the offering of the Securities
         (as those terms are used in Regulation D under the Securities Act) or
         in any manner involving a public offering within the meaning of Section
         4(2) of the Securities Act.

                  (z) None of the Company, its Affiliates or any person acting
         on its or their behalf (other than the Initial Purchasers, as to whom
         the Company makes no representation) has engaged or will engage in any
         directed selling efforts (within the meaning of Regulation S) with
         respect to the Securities and the Company and its Affiliates and any
         person acting on its or their behalf (other than the Initial
         Purchasers, as to whom the


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         Company makes no representation) have complied and will comply with the
         offering restrictions requirement of Regulation S.

                  (aa) Assuming compliance by the Initial Purchasers with their
         representations and warranties set forth in Section 7, it is not
         necessary in connection with the offer, sale and delivery of the
         Securities to the Initial Purchasers in the manner contemplated by this
         Agreement to register the Securities (including the Guarantees) under
         the Securities Act or to qualify the Indenture under the Trust
         Indenture Act of 1939, as amended.

                  (ab) The Securities (including the Guarantees) satisfy the
         requirements set forth in Rule 144A(d)(3) under the Securities Act.

                  (ac) The Company and each Guarantor has complied with all
         provisions of Section 517.075, Florida Statutes (chapter 92-198, Law of
         Florida).

                  (ad) Each of the representations and warranties made in the
         New Credit Facility and the Acquisition Agreements by the Company and
         each of its subsidiaries party thereto is true and correct.

                  (ae) Immediately prior to and after the Closing Date, the
         present fair saleable value of the assets of each Guarantor will exceed
         the amount that will be required to be paid on or in respect of the
         existing debts and other liabilities (including contingent liabilities)
         of such Guarantor as they become absolutely due and matured. The
         Company and each Guarantor believes that the assets of each Guarantor,
         immediately prior to and after the Closing Date, will not constitute
         unreasonably small capital to permit it to carry out its business as
         conducted or as proposed to be conducted. No Guarantor intends to, and
         none believes that it will, incur debts beyond its ability to pay such
         debts as they mature.

                  (af) The Guarantors party hereto (including the Acquired
         Guarantors that will become a party hereto on the Closing Date pursuant
         to the Assumption Agreement) constitute all of the Domestic Restricted
         Subsidiaries (as defined in the Indenture) of the Company as of the
         Closing Date.

                  (ag) The Security Documents will create valid security
         interests or mortgage liens in the collateral purported to be covered
         thereby securing the Company's or relevant Guarantor's obligations
         under the Notes (or, in the case of any Guarantor, its Guarantee),
         which security interests or mortgage liens are and will remain
         perfected security interests or liens prior to all other Liens (subject
         to the exceptions contemplated by the Indenture and the Security
         Documents).

                  (ah) Each of the representations and warranties made by the
         Company and its subsidiaries in each Security Document to which it is a
         party is true and correct.

         2. Agreements to Sell and Purchase. The Company hereby agrees to sell
to the several Initial Purchasers, and each Initial Purchaser, upon the basis of


                                       10
<PAGE>   12
the representations and warranties herein contained, but subject to the
conditions hereinafter stated, agrees, severally and not jointly, to purchase
from the Company the respective principal amount of Securities set forth in
Schedule I hereto opposite its name at a purchase price of 95.572% of the
principal amount thereof plus accrued interest, if any, to the Closing Date (the
"PURCHASE PRICE").

            The Company hereby agrees that, without the prior written consent of
CSFBC on behalf of the Initial Purchasers, it will not, during the period
beginning on the date hereof and continuing to and including the Closing Date,
offer, sell, contract to sell or otherwise dispose of any debt of the Company or
any Guarantor or warrants to purchase debt of the Company or any Guarantor
substantially similar to the Securities (other than the sale of the Securities
under this Agreement).

         3. Terms of Offering. You have advised the Company that the Initial
Purchasers will make an offering of the Securities purchased by the Initial
Purchasers hereunder on the terms to be set forth in the Final Offering
Circular, as soon as practicable after this Agreement is entered into as in your
judgment is advisable.

         4. Payment and Delivery. Payment for the Securities shall be made to
the Company by wire transfer to the account specified by the Company in Federal
or other funds immediately available in New York City against delivery of such
Securities for the respective accounts of the several Initial Purchasers at
10:00 a.m., New York City time, on April 2, 2001, or at such other time on the
same or such other date, not later than April 9, 2001, as shall be designated in
writing by you and the Company. The time and date of such payment are
hereinafter referred to as the "CLOSING DATE."

         Certificates for the Securities shall be in definitive form or global
form, as specified by you, and registered in such names and in such
denominations as you shall request in writing not later than one full business
day prior to the Closing Date. The certificates evidencing the Securities shall
be delivered to you on the Closing Date for the respective accounts of the
several Initial Purchasers, with any transfer taxes payable in connection with
the transfer of the Securities to the Initial Purchasers duly paid, against
payment of the Purchase Price therefor plus accrued interest, if any, to the
date of payment and delivery.

         5. Conditions to the Initial Purchasers' Obligations. The several
obligations of the Initial Purchasers to purchase and pay for the Securities on
the Closing Date are subject to the following conditions:

                  (a) Subsequent to the execution and delivery of this
         Agreement, there shall not have occurred:

                           (i) a change in U.S. or international financial,
                  political or economic conditions or currency exchange rates or
                  exchange controls as would, in the judgment of the Initial
                  Purchasers, be likely to prejudice materially the success of
                  the proposed issue, sale or distribution of the Securities,
                  whether in the primary market or in respect of dealings in the
                  secondary market, or;


                                       11
<PAGE>   13
                           (ii) (A) any change, or any development or event
                  involving a prospective change, in the condition (financial or
                  other), business, properties or results of operations of the
                  Company or its subsidiaries which, in the judgment of a
                  majority in interest of the Initial Purchasers (including
                  CSFBC), is material and adverse and makes it impractical or
                  inadvisable to proceed with completion of the offering or the
                  sale of and payment for the Securities; (B) any downgrading in
                  the rating of any debt securities or preferred stock of the
                  Company by any "nationally recognized statistical rating
                  organization" (as defined for purposes of Rule 436(g) under
                  the Securities Act), or any public announcement that any such
                  organization has under surveillance or review its rating of
                  any debt securities or preferred stock of the Company (other
                  than an announcement with positive implications of a possible
                  upgrading, and no implication of a possible downgrading, of
                  such rating); (C) any suspension or limitation of trading in
                  securities generally on the New York Stock Exchange, or any
                  setting of minimum prices for trading on such exchange or any
                  suspension of trading of any securities of the Company on any
                  exchange or in the over-the-counter market; (D) any general
                  moratorium on commercial banking activities in New York
                  declared by U.S. Federal or New York authorities; or (E) any
                  outbreak or escalation of major hostilities in which the
                  United States is involved, any declaration of war by Congress
                  or any other substantial national or international calamity or
                  emergency if, in the judgment of a majority in interest of the
                  Initial Purchasers (including CSFBC), the effect of any such
                  outbreak, escalation, declaration, calamity or emergency makes
                  it impractical or inadvisable to proceed with completion of
                  the offering or sale of and payment for the Securities.

                  (b) The Initial Purchasers shall have received on the Closing
         Date a certificate, dated the Closing Date and signed by two executive
         officers of the Company and two executive officers of each Guarantor,
         to the effect set forth in Sections 2(l) and 6(a)(ii)(B) (in the case
         of the Company only) and to the effect that the representations and
         warranties of the Company and the Guarantors contained in this
         Agreement are true and correct as of the Closing Date and that the
         Company and the Guarantors have complied in all material respects with
         all of the agreements and satisfied all of the conditions on their part
         to be performed or satisfied hereunder on or before the Closing Date.

                  Each officer signing and delivering such certificate may rely
         upon the best of his or her knowledge as to proceedings threatened.

                  (c) The Initial Purchasers shall have received on the Closing
         Date (i) an opinion of Curtis Mallet-Prevost, Colt & Mosle LLP, outside
         counsel for the Company and the Guarantors, dated the Closing Date,
         substantially in the form set forth in Exhibit A-1 and (ii) an opinion
         of Cardwell and Conner, environmental counsel for the Company and the
         Guarantors substantially in the form set forth in Exhibit A-2:


                                       12
<PAGE>   14
                  (d) The Initial Purchasers shall have received on the Closing
         Date (i) an opinion of Davis Polk & Wardwell, counsel for the Initial
         Purchasers, dated the Closing Date, to the effect set forth in Exhibit
         B and (ii) opinions of Bowles Rice McDavid Graff & Love PLLC, special
         Kentucky and West Virginia counsel for the Initial Purchasers, dated
         the Closing Date, to the effect set forth in Exhibits C-1 and C-2,
         respectively.

                  (e) The Initial Purchasers shall have received on each of the
         date hereof and the Closing Date a letter, dated the date hereof or the
         Closing Date, as the case may be, in form and substance satisfactory to
         the Initial Purchasers, from each of Deloitte & Touche LLP, independent
         public accountants of the Company, and Ernst & Young LLP, independent
         public accountants (with respect to NSA and Xstrata Aluminum Company),
         containing statements and information of the type ordinarily included
         in accountants' "comfort letters" to underwriters with respect to the
         financial statements and certain financial information contained in or
         incorporated by reference into each Offering Circular; provided that
         the letters delivered on the Closing Date shall use a "cut-off date"
         not earlier than the date hereof.

                  (f) (i) Each condition to the closing of the New Credit
         Facility shall have been satisfied (or, with the consent of the Initial
         Purchasers, waived in accordance with the terms of the New Credit
         Facility), (ii) at the Closing Date, no event of default or event that,
         with the giving of notice or lapse of time, or both, would constitute
         an event of default under the New Credit Facility shall have occurred
         and be continuing, and (iii) the closing under the New Credit Facility
         and the borrowing of approximately $4.7 million of loans thereunder in
         connection with the Transactions shall have been consummated, and the
         Initial Purchasers shall have received evidence reasonably satisfactory
         to them of such closing and borrowings.

                  (g) Any amounts outstanding under the Existing Credit Facility
         shall have been repaid in full and such credit facility (as well as
         guarantees thereof and any liens securing such facility) shall have
         been terminated concurrently with the closing hereunder, and the
         Initial Purchasers shall have received evidence reasonably satisfactory
         to them of such repayment and termination.

                  (h) The Company shall have filed the Certificate of
         Designation with the Secretary of State of Delaware (and the same shall
         have become effective and in full force and effect) and shall have
         issued Preferred Stock for gross proceeds of at least $25.0 million,
         and the Initial Purchasers shall have received evidence reasonably
         satisfactory to them of such filing and issuance.

                  (i) (i) Each condition to the closing of the Acquisition and
         the Glencore Sale shall have been satisfied (or, with the consent of
         the Initial Purchasers, waived in accordance with the terms of the
         relevant Acquisition Agreement), and (ii) the closings under the
         Acquisition Agreements (including under the Glencore Disposition
         Agreement) shall have been consummated, and the Initial Purchasers
         shall have received evidence reasonably satisfactory to them of such
         closings.


                                       13
<PAGE>   15
                  (j) The Initial Purchasers shall have received counterparts of
         the Registration Rights Agreement duly executed by the Company and each
         Guarantor.

                  (k) The Notes shall have been designated eligible for trading
         on PORTAL.

                  (l) The Initial Purchasers shall have received copies of (i)
         the New Credit Facility and any related guarantees, security agreements
         and other instruments, (ii) the Acquisition Agreements and each of the
         Related Agreements and any related documents or other instruments,
         (iii) the Owners' Agreement, (iv) each of the New Material Contracts
         and Assigned Material Contracts and (v) the Indenture, in each case
         executed by each of the parties thereto.

                  (m) The Initial Purchasers shall have received fully executed
         original copies of each Security Document and evidence reasonably
         satisfactory to them of the effectiveness of the security contemplated
         thereby and the perfection of the security interests created thereby
         (including the filing of UCC- 1s and arrangements for the recordation
         of any mortgages or deeds of trust.

                  (n) The Initial Purchasers and the Collateral Agent shall have
         received, with respect to each property subject to a Mortgage (i) an
         ALTA extended coverage lender's policy of title insurance in an
         aggregate amount at least equal to $25.0 million, in the case of
         Ravenswood property and $35.0 million, in the case of the Hawesville
         facility, insuring the Mortgage of such property as a valid,
         enforceable first Lien on the applicable Guarantors interest in such
         property as defined in and subject to such Mortgage, subject only to
         permitted encumbrances (as defined in the Indenture), (ii) for each
         policy referred to in clause (i), legible copies of all documents
         affecting title, which shall show all recording information and (iii) a
         survey with respect to such property in form and substance satisfactory
         to the Initial Purchasers and Chicago Title Insurance Company (in the
         case of the Hawesville facility) and First American Title Insurance
         Company (in the case of the Ravenswood facility).

                  Attached to each such policy shall be any and all endorsements
         available in the state in which such property is located, including (1)
         a comprehensive endorsement (ALTA 9 or equivalent) covering
         restrictions and other matters, (2) a 3.1 form of zoning endorsement,
         (3) an endorsement ensuring that the Lien of the Mortgage with respect
         to which the policy is issued is valid against any applicable usury
         laws in the state in which the Property subject to such Mortgage is
         located, (4) an endorsement ensuring that such Property has access to a
         dedicated public street, (5) a contiguity endorsement, (6) a survey and
         "same as" endorsement, (7) an endorsement deleting the so-called "doing
         business" exclusion and (8) a subdivision endorsement.

                  (o) The Initial Purchasers shall have received evidence
         reasonably satisfactory to them that the Company and its subsidiaries
         are


                                       14
<PAGE>   16
         in compliance with the insurance covenants contained in Section 4.04 of
         the Indenture and the Security Documents.

                  (p) The Initial Purchasers shall have received an Assumption
         Agreement in the form of Exhibit D hereto duly executed by each of the
         Acquired Guarantors.

                  (q) The Initial Purchasers shall have received such other
         documents and certificates as are reasonably requested by the Initial
         Purchasers or their counsel.

         6. Covenants of the Company and the Guarantors. In further
consideration of the agreements of the Initial Purchasers contained in this
Agreement, the Company and each Guarantor covenants with each Initial Purchaser
as follows:

                  (a) To furnish to you in New York City, without charge, as
         promptly as practicable on the next Business Day hereafter after the
         execution and delivery hereof and during the period mentioned in
         Section 7(c), as many copies of the Final Offering Circular, any
         documents incorporated by reference therein and any supplements and
         amendments thereto as you may reasonably request.

                  (b) Before amending or supplementing either Offering Circular,
         to furnish to you a copy of each such proposed amendment or supplement
         and not to use any such proposed amendment or supplement to which you
         reasonably object.

                  (c) If, during such period after the date hereof and prior to
         the date on which all of the Securities shall have been sold by the
         Initial Purchasers, any event shall occur or condition exist as a
         result of which it is necessary to amend or supplement the Final
         Offering Circular in order to make the statements therein, in the light
         of the circumstances when the Final Offering Circular is delivered to a
         purchaser, not misleading, or if, in the opinion of counsel for the
         Initial Purchasers, it is necessary to amend or supplement the Final
         Offering Circular to comply with applicable law, forthwith to prepare
         and furnish, at its own expense, to the Initial Purchasers, either
         amendments or supplements to the Final Offering Circular so that the
         statements in the Final Offering Circular as so amended or supplemented
         will not, in the light of the circumstances when the Final Offering
         Circular is delivered to a purchaser, be misleading or so that the
         Final Offering Circular, as amended or supplemented, will comply with
         applicable law. The Initial Purchasers agree to notify the Company of
         the completion of their sale of the Securities.

                  (d) To endeavor to qualify the Securities (including the
         Guarantees) for offer and sale under the securities or Blue Sky laws of
         such jurisdictions as you shall reasonably request; provided that the
         Company will not be obligated to file any general consent to service of
         process or to qualify as a foreign corporation or as a dealer in
         securities in any jurisdiction in which it is not so qualified or to
         subject itself to


                                       15
<PAGE>   17
         taxation in respect of doing business in any jurisdiction in which it
         is not otherwise so subject.

                  (e) Whether or not the transactions contemplated in this
         Agreement are consummated or this Agreement is terminated, to pay or
         cause to be paid all expenses incident to the performance of its
         obligations under this Agreement, including: (i) the fees,
         disbursements and expenses of the counsel and accountants for the
         Company and the Guarantors in connection with the issuance and sale of
         the Securities and all other fees or expenses in connection with the
         preparation of each Offering Circular and all amendments and
         supplements thereto, including all printing costs associated therewith,
         and the delivering of copies thereof to the Initial Purchasers, in the
         quantities herein above specified, (ii) all costs and expenses related
         to the transfer and delivery of the Securities to the Initial
         Purchasers, including any transfer or other taxes payable thereon,
         (iii) the cost of printing or producing any Blue Sky or legal
         investment Offering Circular in connection with the offer and sale of
         the Securities under state securities laws and all expenses in
         connection with the qualification of the Securities for offer and sale
         under state securities laws as provided in Section 7(d) hereof,
         including filing fees and the reasonable and documented fees and
         disbursements of counsel for the Initial Purchasers in connection with
         such qualification and in connection with the Blue Sky or legal
         investment Offering Circular, (iv) any fees charged by rating agencies
         for the rating of the Securities, (v) all document production charges
         and expenses of counsel to the Initial Purchasers (but not including
         their fees for professional services) in connection with the
         preparation of this Agreement that are reasonable and documented, (vi)
         the fees and expenses, if any, incurred in connection with the
         admission of the Securities for trading in PORTAL or any appropriate
         market system, (vii) the costs and charges of the Trustee and any
         transfer agent, registrar or depositary, (viii) the cost of the
         preparation, issuance and delivery of the Securities (including the
         Guarantees), (ix) the costs and expenses of the Company and the
         Guarantors relating to investor presentations on any "road show"
         undertaken in connection with the marketing of the offering of the
         Securities, including, without limitation, expenses associated with the
         production of road show slides and graphics, fees and expenses of any
         consultants engaged in connection with the road show presentations with
         the prior approval of the Company, travel and lodging expenses of the
         representatives and officers of the Company and the Guarantors and any
         such consultants, and the cost of any aircraft chartered with the prior
         approval of the Company in connection with the road show, (x) cost of
         creation and perfection of the security interests under the Security
         Documents (including costs of special Kentucky and West Virginia
         counsel) and all title insurance, recordation charges, filing fees and
         similar costs and expenses, and (xi) all other cost and expenses
         incident to the performance of the obligations of the Company and the
         Guarantors hereunder for which provision is not otherwise made in this
         Section. It is understood, however, that except as provided in this
         Section, Section 9, and the last paragraph of Section 10, the Initial
         Purchasers will pay all of their costs and expenses, including fees and
         disbursements of their counsel (except as provided in clause (x)
         above), transfer taxes payable on resale


                                       16
<PAGE>   18
         of any of the Securities by them and any advertising expenses connected
         with any offers they may make.

                  (f) Neither the Company nor any Affiliate will sell, offer for
         sale or solicit offers to buy or otherwise negotiate in respect of any
         security (as defined in the Securities Act) which could be integrated
         with the sale of the Securities in a manner which would require the
         registration under the Securities Act of the Securities.

                  (g) Not to solicit any offer to buy or offer or sell the
         Securities by means of any form of general solicitation or general
         advertising (as those terms are used in Regulation D under the
         Securities Act) or in any manner involving a public offering within the
         meaning of Section 4(2) of the Securities Act.

                  (h) While any of the Securities remain "restricted securities"
         within the meaning of the Securities Act, to make available, upon
         request, to any seller of such Securities the information specified in
         Rule 144A(d)(4) under the Securities Act, unless the Company is then
         subject to Section 13 or 15(d) of the Exchange Act.

                  (i) None of the Company, its Affiliates or any person acting
         on its or their behalf (other than the Initial Purchasers, as to which
         the Company makes no representation) will engage in any directed
         selling efforts (as that term is defined in Regulation S) with respect
         to the Securities, and the Company and its Affiliates and each person
         acting on its or their behalf (other than the Initial Purchasers, as to
         which the Company makes no representation) will comply with the
         offering restrictions requirement of Regulation S.

                  (j) During the period of two years after the Closing Date, the
         Company will not, and will not permit any of its subsidiaries and will
         use its best efforts to cause its other affiliates (as defined in Rule
         144 under the Securities Act) not to resell any of the Securities which
         constitute "restricted securities" under Rule 144 that have been
         reacquired by any of them except pursuant to an effective registration
         statement under the Securities Act.

                  (k) Not to take any action in violation of Regulation M under
         the Exchange Act in connection with the distribution of the Securities
         contemplated hereby.

         7. Offering of Securities; Restrictions on Transfer. (a) Each Initial
Purchaser, severally and not jointly, represents and warrants that such Initial
Purchaser is a qualified institutional buyer as defined in Rule 144A under the
Securities Act (a "QIB"). Each Initial Purchaser, severally and not jointly,
agrees with the Company that (i) it will not solicit offers for, or offer or
sell, such Securities by any form of general solicitation or general advertising
(as those terms are used in Regulation D under the Securities Act) or in any
manner involving a public offering within the meaning of Section 4(2) of the
Securities Act and (ii) it will solicit offers for such Securities only from,
and will offer such Securities only to, persons that it reasonably believes to
be (A) in the case of


                                       17
<PAGE>   19
offers inside the United States, QIBs and (B) in the case of offers outside the
United States, to persons other than U.S. persons ("FOREIGN PURCHASERS," which
term shall include dealers or other professional fiduciaries in the United
States acting on a discretionary basis for foreign beneficial owners (other than
an estate or trust)) in reliance upon Regulation S under the Securities Act
that, in each case, in purchasing such Securities are deemed to have represented
and agreed as provided in the Final Offering Circular under the caption
"Transfer Restrictions".

         (b) Each Initial Purchaser, severally and not jointly, represents,
warrants, and agrees with respect to offers and sales outside the United States
that:

                  (i) such Initial Purchaser understands that no action has been
         or will be taken in any jurisdiction by the Company that would permit a
         public offering of the Securities, or possession or distribution of
         either Offering Circular or any other offering or publicity material
         relating to the Securities, in any country or jurisdiction where action
         for that purpose is required;

                  (ii) such Initial Purchaser will comply with all applicable
         laws and regulations in each jurisdiction in which it acquires, offers,
         sells or delivers Securities or has in its possession or distributes
         either Offering Circular or any such other material, in all cases at
         its own expense;

                  (iii) the Securities have not been registered under the
         Securities Act and may not be offered or sold within the United States
         or to, or for the account or benefit of, U.S. persons except in
         accordance with Rule 144A or Regulation S under the Securities Act or
         pursuant to another exemption from the registration requirements of the
         Securities Act;

                  (iv) such Initial Purchaser has offered the Securities and
         will offer and sell the Securities (A) as part of their distribution at
         any time and (B) otherwise until 40 days after the later of the
         commencement of the offering and the Closing Date, only in accordance
         with Rule 903 of Regulation S or as otherwise permitted in Section
         8(a); accordingly, neither such Initial Purchaser, its Affiliates nor
         any persons acting on its or their behalf have engaged or will engage
         in any directed selling efforts (within the meaning of Regulation S)
         with respect to the Securities, and any such Initial Purchaser, its
         Affiliates and any such persons have complied and will comply with the
         offering restrictions requirement of Regulation S;

                  (v) such Initial Purchaser has (A) not offered or sold and,
         prior to the date six months after the Closing Date, will not offer or
         sell any Securities to persons in the United Kingdom except to persons
         whose ordinary activities involve them in acquiring, holding, managing
         or disposing of investments (as principal or agent) for the purposes of
         their businesses or otherwise in circumstances which have not resulted
         and will not result in an offer to the public in the United Kingdom
         within the meaning of the Public Offers of Securities Regulations 1995;
         (B) complied and will comply with all applicable provisions of the
         Financial Services Act 1986 with respect to anything done by it in
         relation to the Securities in, from or otherwise involving the United
         Kingdom, and (C) only issued or passed on and will only issue or pass
         on in the United Kingdom any


                                       18
<PAGE>   20
         document received by it in connection with the issue of the Securities
         to a person who is of a kind described in Article 11(3) of the
         Financial Services Act 1986 (Investment Advertisements) (Exemptions)
         Order 1996 or is a person to whom such document may otherwise lawfully
         be issued or passed on;

                  (vi) such Initial Purchaser understands that the Securities
         have not been and will not be registered under the Securities and
         Exchange Law of Japan, and represents that it has not offered or sold,
         and agrees not to offer or sell, directly or indirectly, any Securities
         in Japan or for the account of any resident thereof except pursuant to
         any exemption from the registration requirements of the Securities and
         Exchange Law of Japan and otherwise in compliance with applicable
         provisions of Japanese law; and

                  (vii) such Initial Purchaser agrees that, at or prior to
         confirmation of sales of the Securities, it will have sent to each
         distributor, dealer or person receiving a selling concession, fee or
         other remuneration that purchases Securities from it during the
         restricted period a confirmation or notice to substantially the
         following effect:

                           "The Securities covered hereby have not been
                  registered under the U.S. Securities Act of 1933 (the
                  "Securities Act") and may not be offered and sold within the
                  United States or to, or for the account or benefit of, U.S.
                  persons (i) as part of their distribution at any time or (ii)
                  otherwise until 40 days after the later of the commencement of
                  the offering and the closing date, except in either case in
                  accordance with Regulation S (or Rule 144A if available) under
                  the Securities Act. Terms used above have the meaning given to
                  them by Regulation S."

Terms used in this Section 8(b) have the meanings given to them by Regulation S.

         8. Indemnity and Contribution. (a) The Company and each Guarantor will,
jointly and severally, indemnify and hold harmless each Initial Purchaser, its
partners, directors and officers and each person, if any, who controls such
Initial Purchaser within the meaning of Section 15 of the Securities Act,
against any losses, claims, damages or liabilities, joint or several, to which
such Initial Purchaser may become subject, under the Securities Act or the
Exchange Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon any
untrue statement or alleged untrue statement of any material fact contained in
the Final Offering Circular, or any amendment or supplement thereto, or any
related Preliminary Offering Circular, or arise out of or are based upon the
omission or alleged omission to state therein a material fact necessary in order
to make the statements therein, in the light of the circumstances under which
they were made, not misleading, including any losses, claims, damages or
liabilities arising out of or based upon the Company's failure to perform its
obligations under Section 7(c) of this Agreement, and will reimburse each
Initial Purchaser for any legal or other expenses reasonably incurred by such
Initial Purchaser in connection with investigating or defending any such loss,
claim, damage, liability or action as such expenses are incurred; provided,
however, that the Company and the Guarantors will not be liable in any such case
to the extent that any such loss, claim, damage


                                       19
<PAGE>   21
or liability arises out of or is based upon an untrue statement or alleged
untrue statement in or omission or alleged omission from any of such documents
in reliance upon and in conformity with written information furnished to the
Company by any Initial Purchaser through CSFBC specifically for use therein, it
being understood and agreed that the only such information consists of the
information described as such in subsection (b) below; provided that the
foregoing indemnity agreement with respect to the Preliminary Offering Circular
shall not inure to the benefit of any Initial Purchaser who failed to deliver a
Final Offering Circular (as then amended or supplemented) that was provided by
the Company to the Initial Purchasers in the requisite quantity and on a timely
basis in accordance with Section 7(a) hereof to the person asserting any losses,
claims, damage, liabilities or actions caused by any untrue statement or alleged
untrue statement of material fact or omission or alleged omission to state
therein a material fact, if such untrue statement or alleged untrue statement or
omission or alleged omission was cured in the Final Offering Circular.

         (b) Each Initial Purchaser will severally and not jointly indemnify and
hold harmless the Company and the Guarantors, their respective directors and
officers and each person, if any, who controls the Company or any Guarantor
within the meaning of Section 15 of the Securities Act, against any losses,
claims, damages or liabilities to which the Company or any Guarantor may become
subject, under the Securities Act or the Exchange Act or otherwise, insofar as
such losses, claims, damages or liabilities (or actions in respect there) arise
out of or are based upon any untrue statement or alleged untrue statement of any
material fact contained in the Final Offering Circular, or any amendment or
supplement thereto, or any related Preliminary Offering Circular, or arise out
of or are based upon the omission or the alleged omission to state therein a
material fact necessary in order to make the statements therein, in the light of
the circumstances under which they were made, not misleading, in each case to
the extent, but only to the extent, that such untrue statement or alleged untrue
statement or omission or alleged omission was made in reliance upon and in
conformity with written information furnished to the Company by such Initial
Purchaser specifically for use therein, and will reimburse any legal or other
expenses reasonably incurred by the Company or any Guarantor in connection with
investigating or defending any such loss, claim, damage, liability or action as
such expenses are incurred, it being understood and agreed that the only such
information furnished by any Initial Purchaser consists of (i) the sentence on
the front cover page of the Offering Circulars regarding the delivery of the
Securities, (ii) the third paragraph under "Notice to Investors" on page i of
the Offering Circulars, and (iii) the following information in the Final
Offering Circular furnished on behalf of each Initial Purchaser under the
caption "Plan of Distribution": the first sentence of the third paragraph, the
third and fourth sentences of the eighth paragraph, the ninth paragraph and the
fourth and fifth sentences of the tenth paragraph; provided, however, that the
Initial Purchasers shall not be liable for any losses, claims, damages or
liabilities arising out of or based upon the Company's failure to perform its
obligations under Section 7(c) of this Agreement.

         (c) Promptly after receipt by an indemnified party under this Section
of notice of the commencement of any action, such indemnified party will, if a
claim in respect thereof is to be made against the indemnifying party under
subsection (a) or (b) above, notify the indemnifying party of the commencement
thereof; but the omission so to notify the indemnifying party will not relieve
it from any


                                       20
<PAGE>   22
liability which it may have to any indemnified party otherwise than under
subsection (a) or (b) above unless and to the extent it did not otherwise learn
of such action and such failure results in the forfeiture by the indemnifying
party of substantial rights and defenses. In case any such action is brought
against any indemnified party, the indemnifying party will be entitled to
participate therein and, to the extent that it may wish, jointly with any other
indemnifying party, to assume the defense thereof, with counsel satisfactory to
such indemnified party (who shall not, except with the consent of the
indemnified party, be counsel to the indemnifying party), and after notice from
the indemnifying party to such indemnified party of its election so to assume
the defense thereof, the indemnifying party will not be liable to such
indemnified party under this Section for any legal or other expenses
subsequently incurred by such indemnified party in connection with the defense
thereof other than reasonable costs of investigation. No indemnifying party
shall, without the prior written consent of the indemnified party, effect any
settlement of any pending or threatened action in respect of which any
indemnified party is or could have been a party and indemnity could have been
sought hereunder by such indemnified party unless such settlement includes an
unconditional release of such indemnified party from all liability on any claims
that are the subject matter of such action and does not include a statement as
to or an admission of fault, culpability or failure to act by or on behalf of
any indemnified party.

         (d) If the indemnification provided for in this Section is unavailable
or insufficient to hold harmless an indemnified party under subsection (a) or
(b) above, then each indemnifying party shall contribute to the amount paid or
payable by such indemnified party as a result of the losses, claims, damages or
liabilities referred to in subsection (a) or (b) above (i) in such proportion as
is appropriate to reflect the relative benefits received by the Company and the
Guarantors on the one hand and the Initial Purchasers on the other from the
offering of the Securities or (ii) if the allocation provided by clause (i)
above is not permitted by applicable law, in such proportion as is appropriate
to reflect not only the relative benefits referred to in clause (i) above but
also the relative fault of the Company and the Guarantors on the one hand and
the Initial Purchasers on the other in connection with the statements or
omissions which resulted in such losses, claims, damages or liabilities as well
as any other relevant equitable considerations. The relative benefits received
by the Company and the Guarantors on the one hand and the Initial Purchasers on
the other shall be deemed to be in the same proportion as the total net proceeds
from the offering (before deducting expenses) received by the Company and the
Guarantors bear to the total discounts and commissions received by the Initial
Purchasers from the Company under this Agreement. The relative fault shall be
determined by reference to, among other things, whether the untrue or alleged
untrue statement of a material fact or the omission or alleged omission to state
a material fact relates to information supplied by the Company or any Guarantor
or the Initial Purchasers and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such untrue statement or
omission. The amount paid by an indemnified party as a result of the losses,
claims, damages or liabilities referred to in the first sentence of this
subsection (d) shall be deemed to include any legal or other expenses reasonably
incurred by such indemnified party in connection with investigating or defending
any action or claim which is the subject of this subsection (d). Notwithstanding
the provisions of this subsection (d), no Initial Purchaser shall be required to
contribute any amount in excess of the amount by


                                       21
<PAGE>   23
which the total discounts and commissions received by such Initial Purchaser
exceeds the amount of any damages which such Initial Purchaser has otherwise
been required to pay by reason of such untrue or alleged untrue statement or
omission or alleged omission. The Initial Purchasers' obligations in this
subsection (d) to contribute are several in proportion to their respective
purchase obligations and not joint.

         The Company, the Guarantors and the Initial Purchasers agree that it
would not be just and equitable if contribution pursuant to this Section were
determined by pro rata allocation (even if the Initial Purchasers were treated
as one entity for such purpose) or by any other method of allocation which does
not take account of the equitable considerations referred to above in this
Section. No person guilty of fraudulent misrepresentation (within the meaning of
Section 11(f) of the Securities Act) shall be entitled to contribution from any
person who was not guilty of such fraudulent misrepresentation.

         (e) The obligations of the Company and the Guarantors under this
Section shall be in addition to any liability which they may otherwise have and
shall extend, upon the same terms and conditions, to each person, if any, who
controls any Initial Purchaser within the meaning of the Securities Act or the
Exchange Act; and the obligations of the Initial Purchasers under this Section
shall be in addition to any liability which the respective Initial Purchasers
may otherwise have and shall extend, upon the same terms and conditions, to each
person, if any, who controls the Company or any Guarantor within the meaning of
the Securities Act or the Exchange Act.

         9. Effectiveness; Defaulting Initial Purchasers. This Agreement shall
become effective upon the execution and delivery hereof by the parties hereto.

         If, on the Closing Date, any one or more of the Initial Purchasers
shall fail or refuse to purchase Securities that it or they have agreed to
purchase hereunder on such date, and the aggregate principal amount of
Securities which such defaulting Initial Purchaser or Initial Purchasers agreed
but failed or refused to purchase is not more than one-tenth of the aggregate
principal amount of Securities to be purchased on such date, the other Initial
Purchasers shall be obligated severally in the proportions that the principal
amount of Securities set forth opposite their respective names in Schedule I
bears to the aggregate principal amount of Securities set forth opposite the
names of all such non-defaulting Initial Purchasers, or in such other
proportions as you may specify, to purchase the Securities which such defaulting
Initial Purchaser or Initial Purchasers agreed but failed or refused to purchase
on such date; provided that in no event shall the principal amount of Securities
that any Initial Purchaser has agreed to purchase pursuant to this Agreement be
increased pursuant to this Section 10 by an amount in excess of one-ninth of
such principal amount of Securities without the written consent of such Initial
Purchaser. If, on the Closing Date any Initial Purchaser or Initial Purchasers
shall fail or refuse to purchase Securities which it or they have agreed to
purchase hereunder on such date and the aggregate principal amount of Securities
with respect to which such default occurs is more than one-tenth of the
aggregate principal amount of Securities to be purchased on such date, and
arrangements satisfactory to you and the Company for the purchase of such
Securities are not made within 36 hours after such default, this Agreement shall
terminate without liability on the part of any


                                       22
<PAGE>   24
non-defaulting Initial Purchaser or of the Company. In any such case either you
or the Company shall have the right to postpone the Closing Date, but in no
event for longer than seven days, in order that the required changes, if any, in
the Final Offering Circular or in any other documents or arrangements may be
effected. Any action taken under this paragraph shall not relieve any defaulting
Initial Purchaser from liability in respect of any default of such Initial
Purchaser under this Agreement.

         If this Agreement shall be terminated by the Initial Purchasers, or any
of them, because of any failure or refusal on the part of the Company to comply
with the terms or to fulfill any of the conditions of this Agreement, or if for
any reason the Company shall be unable to perform its obligations under this
Agreement, the Company will reimburse the Initial Purchasers or such Initial
Purchasers as have so terminated this Agreement with respect to themselves,
severally, for all out-of-pocket expenses (including the fees and disbursements
of their counsel) reasonably incurred and documented by such Initial Purchasers
in connection with this Agreement or the offering contemplated hereunder.

         10. Counterparts. This Agreement may be signed in any number of
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

         11. Applicable Law. This Agreement shall be governed by and construed
in accordance with the internal laws of the State of New York.


                                       23
<PAGE>   25
         12. Headings. The headings of the sections of this Agreement have been
inserted for convenience of reference only and shall not be deemed a part of
this Agreement.


                                       24
<PAGE>   26
                                  Very truly yours,

                                  CENTURY ALUMINUM COMPANY


                                  By:
                                          --------------------------------------
                                          Name:
                                          Title:


                                  CENTURY ALUMINUM OF WEST
                                  VIRGINIA, INC.


                                  By:
                                      --------------------------------------
                                      Name:
                                      Title:


                                  BERKELEY ALUMINUM, INC.


                                  By:
                                      --------------------------------------
                                      Name:
                                      Title:


                                  CENTURY KENTUCKY, INC.


                                  By:
                                      --------------------------------------
                                      Name:
                                      Title:

                                  VIRGIN ISLANDS ALUMINA
                                  CORPORATION LLC


                                  By:
                                      --------------------------------------
                                      Name:
                                      Title:


                                       25
<PAGE>   27
Accepted as of the date hereof

CREDIT SUISSE FIRST BOSTON
        CORPORATION
FLEET SECURITIES, INC.

By: Credit Suisse First Boston Corporation



By:
    -------------------------------------
    Name:
    Title:


                                       26
<PAGE>   28
                                                                      SCHEDULE I

<TABLE>
<CAPTION>
                                                        PRINCIPAL AMOUNT OF
                INITIAL PURCHASER                   SECURITIES TO BE PURCHASED
------------------------------------------------    --------------------------
<S>                                                 <C>
Credit Suisse First Boston Corporation..........          $292,500,000
Fleet Securities, Inc. .........................          $ 32,500,000
                                                          ------------

            Total:..............................          $325,000,000
                                                          ============
</TABLE>
<PAGE>   29
                                                                     SCHEDULE II


                                  SCHEDULE II-A
                           EXISTING MATERIAL CONTRACTS

1.       Molten Aluminum Purchase Agreement between Century Aluminum of West
         Virginia, Inc. and Pechiney Rolled Products, LLC, dated September 20,
         1999

2.       Aluminum Purchase Agreement between Berkeley Aluminum, Inc. and
         Glencore Ltd., dated April 7, 2000

3.       Alumina Supply Agreement dated June 26, 1996 between Glencore AG and
         Berkeley Aluminum, Inc., as assignee of Glencore Primary Aluminum
         Company LLC

4.       Alumina Supply Agreement between Alcoa Alumina & Chemicals, L.L.C.,
         Alcoa of Australia, Ltd., and Century Aluminum of West Virginia, Inc.
         (f/k/a, Ravenswood Aluminum Corporation), dated July 24, 1995

5.       Alumina Supply Agreement, dated as of January 1, 2001, between Glencore
         Ltd. and Berkeley Aluminum, Inc.

6.       Alumina Supply Agreement, dated as of January 1, 2001, between Glencore
         AG and Century Aluminum of West Virginia, Inc.

7.       Limited Term Firm Power Supply Agreement between Ravenswood Aluminum
         Corporation and Ohio Power Company, dated July 1, 1996; as amended by
         Amendment No. 1 dated January 13, 1997

8.       South Carolina Public Service Authority Service Agreement for Large
         Power Electric Service between the South Carolina Public Service
         Authority and Alumax of South Carolina, Inc., dated July 1, 1997

9.       Mt. Holly Owners Agreement


                                  SCHEDULE II-B
                             NEW MATERIAL CONTRACTS

1.       Aluminum Supply Agreement between Century Aluminum Company and
         Southwire Company, dated as of the Closing Date
<PAGE>   30
                                  SCHEDULE II-C
                           ASSIGNED MATERIAL CONTRACTS

1.       1998 Settlement Agreement among Alcan Aluminum Corporation, Southwire
         Company, Big Rivers Electric Corporation, LG&E Energy Corp., Rural
         Utility Services, Henderson, Union Rural Electric Cooperative Corp.,
         Green River Electric Corporation, and The Bank of New York, dated July
         15, 1998, as assigned to Century or one of its subsidiaries pursuant to
         the assignment and assumption agreement dated as of the Closing Date

2.       Alumina Purchase Agreement between Kaiser Aluminum, Chemical
         Corporation and Southwire Company, dated December 18, 1997 as amended
         heretofore by First Amendment and Second Amendment, as assigned to
         Century or one of its subsidiaries pursuant to the assignment and
         assumption agreement dated as of the Closing Date

3.       Agreement for Electric Service between Green River Electric Corporation
         and Southwire Company, dated July 15, 1998, as amended by Amendment No.
         1 dated July 15, 1998 and including all Third-Party Supplier Agreements
         as described in Schedule A thereto, as assigned to Century or one of
         its subsidiaries pursuant to the assignment and assumption agreement
         dated as of or prior to the Closing Date


                                       2
<PAGE>   31
                                                                    SCHEDULE III


                               SECURITY DOCUMENTS

1.       Pledge and Security Agreement, dated as of the Closing Date, among the
         Company, the other Pledgors party thereto and Wilmington Trust Company,
         as collateral agent (the "COLLATERAL AGENT") relating to the pledge of
         cash collateral held in a cash collateral account.

2.       Deed of Trust, Assignment of Leases and Rents, Security Agreement and
         Financing Statement dated as of the Closing Date from Century Aluminum
         of West Virginia, Inc. for the benefit of the Collateral Agent relating
         to the Ravenswood, WV facility.

3.       Mortgage Assignment of Leases and Rents, Security Agreement and
         Financing Statement dated as of the Closing Date from NSA, Ltd. for the
         benefit of the Collateral Agent relating to the Hawesville, KY
         facility.


                                       3
<PAGE>   32
                                   Schedule A

              1. Mortgage, Assignment of Leases and Rents, Security Agreement
and Financing Statement dated as of April 2, 2001 from NSA, Ltd. as the
mortgagor, to Wilmington Trust Company as the mortgagee, and Collateral Agent,
relating to the property near Hawesville, Kentucky, to be filed for record in
the Office of the Recorder in Hancock County, Kentucky.
<PAGE>   33
                                   Schedule B

                              Financing Statements

              1. Financing Statement on form UCC-1 listing the Mortgagor as
debtor and the Collateral Agent as secured party, relating to the Hawesville
Kentucky Property to be filed in the Office of the Recorder in Hancock County,
Kentucky.

              2. Financing Statement on form UCC-1 listing the Mortgagor as
debtor and the Collateral Agent as secured party, relating to the Hawesville
Kentucky Property to be filed in the Office of the Secretary of State of the
State of Kentucky.
<PAGE>   34
                                   Schedule A

              1. Deed of Trust, Assignment of Leases and Rents, Security
Agreement and Financing Statement dated as of April 2, 2001 from Century
Aluminum of West Virginia, Inc. as the grantor, to Wilmington Trust Company as
the grantee, and Collateral Agent, relating to the property near Jackson County,
West Virginia, to be filed for record in the office of the Clerk of County
Commission of Jackson County, West Virginia.
<PAGE>   35
                                   Schedule B

                              Financing Statements

              1. Financing Statement on form UCC-1 listing the Grantor as debtor
and the Collateral Agent as secured party, relating to Jackson County West
Virginia Property to be filed in the office of the Clerk of the County
Commission of Jackson County, West Virginia.

              2. Financing Statement on form UCC-1 listing the Grantor as debtor
and the Collateral Agent as secured party, relating to the Jackson County West
Virginia Property to be filed in the Office of the Secretary of State of the
State of West Virginia.
<PAGE>   36
                                                                       EXHIBIT D



                              ASSUMPTION AGREEMENT



             Each of the undersigned, which has become a subsidiary of Century
Aluminum Company (the "COMPANY") as of the date hereof, hereby expressly
assumes, and agrees to perform and discharge, all of the obligations and
liabilities of a "Guarantor" under the Purchase Agreement (the "PURCHASE
AGREEMENT") dated March 28, 2001 among the Company, the Guarantors party thereto
and Credit Suisse First Boston Corporation and Fleet Securities, Inc., as
Initial Purchasers, including without limitation, the indemnity and contribution
obligations under the Purchase Agreement. All references in the Purchase
Agreement to the "Guarantors" shall hereafter refer to the Guarantors party
thereto, as well as each of the undersigned and its respective successors.

            IN WITNESS WHEREOF, each of the undersigned has caused its duly
authorized officer to execute and deliver this Assumption Agreement as of April
2, 2001.


                                           METALSCO, LTD.



                                           By:________________________________
                                              Name:
                                              Title:

                                           SKYLINER, INC.



                                           By:________________________________
                                              Name:
                                              Title:

                                           NSA, LTD.



                                           By:________________________________
                                              Name:
                                              Title:


                                      D-1